Question

Which has the strongest and weakest ionic bonds among the following?
$LiI,NaI,KI,CsI$

• A. $KI,NaI$
• B. $CsI,LiI$
• C. $KI,LiI$
• D. $CsI,NaI$

Answer 1

The correct option is B $CsI,LiI$

In $LiI$, lattice energy of $Li$ is more than $Cs$ in $CsI$. Moreover lattice energy is inversely proportional to the atomic radii. Hence, $LiI$ will have the strongest ionic bond and $CsI$ the weakest.